Improved islet yields after purification following the novel endogenous trypsin inhibitor and histidine-tryptophan-ketoglutarate treatment in pigs.
BACKGROUND
Adult porcine islet xenotransplantation into humans is greatly diminished by the difficulty to isolate islets because of their fragility. The goal of this study was to improve the efficacy of islet yields using endogenous trypsin inhibitor and histidine-tryptophan-ketoglutarate (HTK) perfusate.


METHODS
We compared two porcine islet isolation protocols: Eurocollins solution for in situ pancreas perfusion without use of an endogenous trypsin inhibitor versus HTK solution including endogenous trypsin inhibitor for pancreas perfusion.


RESULTS
Endogenous trypsin inhibitor and HTK strategies significantly improved total islet yield, recovery, and islet index after purification (P < .05), whereas unpurified islet yield did not increase. An average of 228,000 +/- 95,000 islet equivalents (IEQ) (n = 20) purified islets were obtained in the first group compared with 115,000 +/- 56,000 IEQ (n = 18) in the second group. The average islet index was significantly increased in the first group compared with the second group before and after purification: before: 0.28 versus 0.49 versus after: 0.25 versus 0.4 (P < .05). At this time, islet purity, viability, and stimulation index did not show a significant difference between groups.


CONCLUSIONS
Our study showed that endogenous trypsin inhibitor and HTK strategies significantly improved purified islet isolation efficacy because of reduction of islet fragility.
Wee
Y M
YM
Asan Institute for Life Science, Seoul, Korea.
Kim
S C
SC
Koo
S K
SK
Kim
Y H
YH
Jung
E J
EJ
Choi
M Y
MY
Park
Y H
YH
Park
K T
KT
Lim
D G
DG
Han
D J
DJ
D000818:Animals; D002469:Cell Separation / Q000379:methods; D005947:Glucose / Q000494:pharmacology; D006982:Hypertonic Solutions / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D008353:Mannitol / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D011343:Procaine / Q000494:pharmacology; D013552:Swine; D014361:Trypsin Inhibitors / Q000494:pharmacology*
C039984:Bretschneider cardioplegic solution; D006982:Hypertonic Solutions; D007328:Insulin; D014361:Trypsin Inhibitors; D008353:Mannitol; D011343:Procaine; D011189:Potassium Chloride; D005947:Glucose